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Nurikabe rules

The rules to Nurikabe are actually quite simple, but they combine together to give some wonderful logic problems. The challenge is to construct a maze (where the white squares are the walls), that satisfy these rules,
  1. The walls are made of connected adjacent stone blocks.
  2. The squares with numbers in them are part of a wall. That particular wall must contain exactly that number of squares, e.g. A square with the number 4 in it means that it forms a wall with 3 other squares.
  3. Walls may not touch each other, even if they have the same number (diagonally is fine).
  4. All the squares that are not part of the wall make up the maze.
  5. The maze must be one single connected whole, i.e. from any black starting square, you must be able to reach any other black square by only moving to adjacent black squares. Diagonal moves are not allowed.
  6. The maze can't contain any 2*2 'rooms'
A completed Nurikabe puzzle,
From this set of rules, we can make a few deductions,
These rules take a little bit of getting used to, but once you are familiar with them, Nurikabe puzzles offer a good alternative to the more mainstream logic puzzles such as Sudoku. Want to see how these rules are applied to solve a Nurikabe puzzle?